Inorganic pigments are used as opacifiers and colorants in various applications including coating (for example, ink and paint), plastic and paper applications. The effectiveness of inorganic pigments in such applications depends in part on how evenly the pigment can be dispersed in the respective base composition (for example, a polymer composition).
In order to facilitate even distribution of inorganic pigments into base compositions, the pigments are typically formed into finely divided powders. For example, the particle size of a pigment can be reduced by milling or micronizing the pigment during the finishing steps of the pigment manufacturing process.
Unfortunately, pigment powders tend to be dusty and exhibit poor flow characteristics. These issues can make the pigment powders difficult to bag and transport and create problems in forming, compounding and manufacturing end-use products. The poor flow characteristics of the pigment particles can make the amount of time and energy needed to sufficiently disperse the particles into base compositions excessively high. Dispersion of pigment powders into polymer compositions can be particularly problematic.
Increasing the ability of inorganic pigments to be dispersed into base compositions makes the pigments more suitable for end use applications.